This project is centered around the bacterial motor and its modulation by sensory information from the environment. The relationship between changes in external pH and the regulation of internal pH will be examined by 31P NMR, and the consequences of internal pH changes upon the chemotaxis methylation system and the motor will be studied. Fractionation of components of the bacterial motor will be attempted. Most proteins (needed for motor function) have been placed on a plasmid under control of the lambda promotor; amplified production of these proteins is being attempted with a view to physically characterizing them.